Fàbregas was involved in a collision with John Terry early in the second half of the hosts’ 1-0 win and was withdrawn after 50 minutes to be replaced by Ramires. José Mourinho had initially suggested his withdrawal was merely precautionary with one eye on the visit of the champions but the Spaniard underwent treatment on Wednesday and is rated highly doubtful for Saturday’s Premier League game.

His fitness will continue to be monitored over the remainder of the week though the initial prognosis is far from encouraging. His absence would represent a considerable blow given Fàbregas’s hugely positive impact – as a goal provider – since returning to English football from Barcelona last summer.

Chelsea are already likely to be without Costa, who has scored 17 goals in 19 Premier League appearances since his £32m move from Atlético Madrid, against City after the Brazilian-born forward was charged with violent conduct after appearing to stamp on Emre Can early in Tuesday’s win.

Of the other Chelsea players hurt on Tuesday, Filipe Luís succumbed to a calf complaint and is likely to be replaced by César Azpilicueta against City, while Branislav Ivanovic suffered a badly cut foot but should be fit enough to feature.

Didier Drogba is likely to stand in for Costa if the striker chooses not to contest the violent conduct charge or if his appeal is rejected by an independent commission on Friday. At present he will miss the games against City, Aston Villa and Everton.